When the dishwasher is draining the water comes out airgap hole but disposal drains fine.

You may have a clog or kink in the hose between the Airgap and the disposal, remove the hose attached to Airgap and disposal see the Image check for obstruction clean the hose, also check the port of the G/D where the hose connects if the plug is removed, install the hose and check hope you be OK, good Luck.

John